Telephone set.



W. P. ANDFHCK.

TELEPHONE SET.

APPLICATION FILED Aue.2l2. 191;..

Patented Aug. l?. i915.

awa.. muy

I tothe coils 9 and 10 ofthe telephone rewhen energized by' the' tio'n soas to constitute north and south poles when energized. These coils are .adapted to act upon t e diaphragm toavibrate the. same .ters are of the well known type used with f Acousticonwoutts and their special struc,-v

fture vforms no part of the present-invention, for .which :reason they have been illustra-ted only diagrammatically.` As' shown, the senstive'transmitter. 13 is connected in shunt with ,the sensitive transmitter .12 by means of wires-14 and 1'5, While both transmitters are connected by -a common circuit,N

ceiv'er bymeans of wire 16, battery '17 and wires 18 and 19, the circuit passlng through thecoils 9 and l0 yin series-and the coils being wound in suchva manner that the flux set up in these coils will be in opposite directions to form'the north and southpoles 'of the electromagnet. With thisform of connection, if for example the sensitive transmitter 12, is being actuated, vwhile. the sensi- 'tive transmitter 13 is at rest, whichoccurs when the transmitters are arranged inV different planes as in the vform'of apparatus shown inthe patent to Turner referred to, the Wires 14 and 15, together with the sensitivetransmitter 13, forms a shunt circuit around the sensitive transmitter-12, lwhich will permit a large'p'art of the pulsating currentto flow through .the same, instead of over Wires 16, ybattery 17, to the wire 18,

to the [coils 9 and 10 ofthe receiver. The reason that part lof the pulsatingcurrent takes this shunt path is in all probabilities explained by the factthatthe coils 9 and 10 have a rrelatively high impedance and therefore to some extent act as a reactance coil to retard the flow 'of pulsating currentD through the same, and- While although the resistance of transmitter 13V is relatively high yet it is non-inductive so that a relatively large amount of the pulsating current set up will pass through the same. The result is a Weakeningof the intensity of the sounds which emanate from the receiver. This signe result is alsov apparent even if both -transmitters12/Qand 13 -are arranged in the same plane 'and are vboth being actuated, since the'lcircui'tsthrough each of the transmitters ac tsas a shunt for the other.

Fig. 4 'shows'cnc system .of` circuits and form of z"telephone recelver `for avoiding shunting the pulsating current. through the circuit'of the ,other transmitters. y

As in thejusual form oftelephone receiver, the electro-magnet consists of 'two coils orv pulsating current two .circuits is practically spectively 9*l and 10, but here the windings instead of being connected in series are separate.- The sensitive transmitters 12 and 13v I are each connected to one of these windings;

sensitive transmitter 12 is connectedA by means of wire 2Qto coil 10, whilesensitive transmitter 13 is'connected to coil 9'L` through wlre 21. Wires 23 and,24,respectively, connect transmitters-12 E-'nd 13., in parallel to a common path or' circuit comprising wire 25, battery 17 and wire 26. Here the circuit againbranches, the coils 9I andl 10* being' respectively connected towire 26 by wires 27. and 28- so that the current will kpass through, the coils in opposite directions and the iux setup in the coils will form the north and south poles of the electromagnet .as in the present form of telephone receiver. It has been found that when thisA arrangement of circuits and form of telephone re-` emanating ceiver is. employed, the sounds from the receiver are materiallyr louder-in tone thanvthe sounds ywhich are obtained when-the present form of connection shown'- in Fig. 3 1s used.` This is probably d'ue to the factthat the entirestrength oipulsating currentproduced by the'.actuationffof one orboth 'of thetransmitters passes throu h the "coils of the telephone receiver. If, or

example, transmitter'12 is beingactuated to A set up a pulsating current, the same may take `two paths; one through wire 2 battery 17 wires 26 and 27,- coil '10 an Wire 20 back to the transmitter; A.and another through wire 23, 25 and battery 17 as before to wire 26, and then through 'wire-28, coil 9?, wire 21, transmitter 13, and "wire 24' back to wire 25; -The impedance of these the same as they both include one of the coils of the receiver. The major portion of the pulsating current will pass through coil 10l as the resistance 'f A .of transmitter 13, when at rest, ismateria'lly greater than 12 when the same is being actuated. However, the portion of pulsating current passing through the circuit including a transmitter 13 and coil 9IL will energize this coil to aid the coil 10 in attracting the diaphragm. If both transmitters should b'e actuated simultaneously, practically' the samc result is obtained as the pulsating curthrough its "corresponding circuit.

ment and manner ofv connecting separate 4rent 'set' up by each transmitter passes windings of the receiver to each ofthe indil vidual transmitters. Each of the sensitive transm1tters12 and 13 1s connected to a which. have' been designated 9* and 10" -=re- Separate'section of eachf'of the coils and',125

:i separare r:

are Honnef Lf) iixii Lim muis is wir n pini neced 'by :i separate cireui; to separate coils nr windings of the eiec-nmngjnet in the telethe invention to i arrangements sh particular circuit ony by the scope i feto, wherein the ni ine snicently ne Ur n plurality of coils rzinsniiter.

e. sei; 'comprising a. telephone :i phn'aiy 'of separate ziiiry of transmitters' and respectively connecting @infix 'si seid rzinsmitters to different Windings of smid receiver. l

2. A. tecpnone set comprising a telephone receiver having :i plurality of separate windings und :i pluruity of telephone transauch :i1-ranged in serieswith diifer- @ni windings of said receiver.

:3. A nephone set. comprising a. telephone fii'vrvr having a phirniity of separate wind- :i ,nlurnity of telephone transmitters,

wlmi in number to vthe number of windings.

nini Huil-gram circuits connecting @zich transniitifr :inseries with :i .unrrespmiding winding in 'he receiver.

."i @ci-opium@ svt comprising :i iden-iron, rcrvivci; having :i plurality of separate minding, u purziiitf.'Y ui transmitters, cire miti mnncring i I trnnsznittr to :i con i'magxffniing* winding` in ne receiver, Suid cirvfziie ming' mnneffzed n said windings 1.0 gn'nsurv north unil rimiii poles.

in, ii'itnvss iwi-vnl". i subscribe my signalwere, in tir prisvnuyof tw() winesses.

WIUJLACE i. N DRTCK.

Wi messes:

Hmmm Mawr), (han. E?. THOMAS.

ne receiver and i@ is nov my intention -to- 

